Hate my MIL - bad gender reveal

JJ

Did a small gender reveal today (it’s Canadian thanksgiving so we’re off work and with family so we figured why not) we did one on sat with my side, it went great, so much fun, great pictures, today we did it with my husbands, gave my MIL a confetti cannon and said let’s all go in the backyard and shoot it off, I’ll take some pictures. Without even noticing she walked right out the back door while we were all putting jackets/boots on to go outside, she shoots it off by herself outside, comes back in and says “ugh I wanted it to be a girl and I wanted to name her Sadie!” WHAT THE ACTUAL FUCK. So obviously it’s a boy, the whole family missed the confetti and it was like a SLAP across the face to see her so disappointed with the gender. And excuse me “you wanted to name her Sadie” ??? Who does she think she is? My husband was SO pissed we literally packed up our shit and left, skipped dinner. We thought we were doing a nice thing involving her and letting HER be the one to do the reveal in front of her whole family. We had also told them right before that for the last month my doctor suspected the baby had Down’s syndrome, we were explaining to them how LITTLE we cared about gender at this point because we just got results back saying baby didn’t have downs so we’re just grateful for a healthy baby. Apparently MIL is not.